We studied the spatial and temporal tuning properties of primary motor cortex (MI) arm area neurons using a visually-guided continuous tracking task. A chronically implanted multielectrode array was used to record from 4-21 neurons simultaneously during task performance. The task requires manual tracking of a smoothly moving target which follows a random trajectory, and allows control over the statistical properties of arm motion in 3 principal ways: dense sampling of the workspace; independence of hand position and velocity; and stationarity of behavioral and neural variables. MI tuning functions were heterogeneous across a simultaneously recorded population, varying along a continuum from predominantly hand velocity tuning to chiefly position tuning. Both the timing and amount of information about hand trajectory varied across neurons. Though the information content for velocity and position were ~equal and small, they ranged over 2 orders of magnitude across the population. Velocity information typically peaked about 100ms before the behavior, while information about hand position could peak prior to and/or following the behavior, suggesting that position tuning may be a function of both preparatory signals and feedback. The individual firing rates from a small group of neurons could be linearly combined to reconstruct any random hand trajectory, but only for low frequencies of motion(<0.5Hz).